1. Field of the Invention
The present invention relates to an adjustable head wrench which may be attached to a socket wrench handle, to a power tool or as an integral part of a power tool. It uniquely provides for adjustment of size for rotation of hexagonal fasteners, while providing for all six flat surface contacts and three symmetrical point-to-point contacts during operation.
2. Information Disclosure Statement
The following patents represent various types of adjustable wrench arrangements:
U.S. Pat. No. 4,136,588 to Peter G. Roder describes an aligned sliding jaw key set for use with any standard ratchet wrench. The device is adaptable to being made up in kits that include three jaw keys in different sizes so that they replace nine to twelve solid sockets of different sizes in metric and American standards. Each of the jaw keys has a set of jaws each one of which is provided with an angular gripping portion able to fit and hold tightly onto the sides of nuts and bolts.
U.S. Pat. No. 4,366,733 to David S. Colvin describes a socket for torquing nuts and bolt heads which includes adjustable jaws biased in an outward radial direction by associated helical springs whose inner ends are engaged with a seat preferably embodied by a ball. A support member includes slideways that mount slides of the jaws for inward and outward adjusting movement, and each jaw has an inwardly facing engagement surface inclined with a slight inward inclination in an axial direction away from the slide thereof so as to accommodate for clearance between the slide and the associated slideway by jaw tilting that permits gripping of a nut or bolt head with surface-to-surface contact. A camming surface on each jaw is engaged by a camming surface on a sleeve of the socket and defines an angle greater than 90xc2x0 with the path of jaw movement so as to facilitate jaw adjustment and prevent any binding of the jaws during such adjustment.
U.S. Pat. No. 4,520,698 to Werner W. Martinmaas describes an adjustable socket for a socket wrench or the like which has a body member with two side plates, and between the side plates are jaw members which are concurrently movable parallel to the side plates to adjust the space between confronting jaw elements on the free ends of the jaw members. Pin and slot connections are used to change the positions of the jaw members. One embodiment of the invention provides for automatic adjustment when the socket is pushed against a hex-head fastener; and a second embodiment provides for manual adjustment by sliding an operating yoke forwardly on the body member.
U.S. Pat. No. 4,676,125 to Jeffrey L. Ardelean describes an improved adjustable socket for use with a ratchet wrench drive handle to loosen or tighten bolts, nuts and other threaded workpieces, which is comprised of a hollow cylindrical casing having a passive end adapted to receive a wrench handle protuberance, an opposing work end adapted to fit about a workpiece and a sidewall interconnecting such ends with one another and defining a cavity therebetween. A plurality of uniformly spaced apart through-openings are provided in the casing sidewall between the opposing ends thereof and a cylindrically shaped gripping member is pivotally mounted along a vertical eccentric axis thereof within each through-opening so as to be selectively moveable into and out of the casing cavity. In use, the adjustable socket is mounted onto a wrench handle and positioned about a threaded workpiece. An adjustment ring is then rotatably moved, say downwardly, so that a beveled surface thereof contacts a corresponding beveled surface of each gripping member and causes each gripping member to radially move inwardly into the casing cavity whereby a convex work face of each gripping member contacts the periphery of the workpiece. Upon application of torque to the wrench handle, each work face is continually urged into intimate gripping contact with the workpiece so as to drive it in a desired direction. Upon release/reversal of the torque force and upward movement of the adjustment ring, each gripping member is urged, via a biasing means, radially outwardly of the casing cavity so as to disengage from the workpiece.
U.S. Pat. No. 4,864,901 to Don le Duc describes and adjustable wrench socket of the screw adjustment type in which two identical jaws facing each other have a multiple non-slip grip on nut and screw heads and in which the jaw movements are synchronized in respect to the axis of their mutual housing that slidably engages them but controls them in all other unwanted directions and further provides for adaptability to commercial drives and their extensions.
U.S. Pat. No. 4,884,480 to Tim K. Briese describes an adjustable socket which provides continuous sizing from a minimum opening to a maximum opening to accommodate differently sized nut structures. The socket includes a socket body having a head portion and a pair of longitudinal wing portions separated by a channel region defined by a slideway region and a keyway region. A pair of jaw members are provided, each having a slide element received in the keyway region for transverse reciprocal movement and a jaw element projecting longitudinally of its slide element and received in the slideway region. When mounted, the jaw elements have facing interior work faces and oppositely facing, exterior cam surfaces. The wing portions are externally threaded and threadably receive a collar. Biasing springs apply restorative force tending to separate the jaw elements to open the region between the work faces. The collar bears against the cam surfaces and acts in constraining opposition to the biasing springs whereby constrained selective adjustment of the opening for the nut structure is obtained. The slide elements are otherwise freely slidable transversely in the keyway region, but they include interlock structure to prevent longitudinal movement in the socket body. An indexed area may cooperate with the collar to indicate the nut structure opening size in conventional units.
U.S. Pat. No. 4,892,016 to J. E. C. Anderson describes an adjustable socket having a driver rotatably driveable about a central axis, wherein the driver includes inclined slideways extending with both radial and axial components with respect to the central axis. Jaws are supported within corresponding slideways of the driver for movement with respect to the central axis. The jaws each include an internal driver aperture having an axis transverse to the central axis. An adjuster provided with the socket includes a jaw operating member, jaw clips and a connection that secures the jaws, jaw operating member and jaw clips to maintain the socket in the assembled condition and to limit inward movement of the jaws. The jaw operating member includes an annular flange projecting outwardly in a radial direction with respect to the central axis to axially locate the jaw clips. Mating helical surfaces support the adjuster on the driver for axial adjusting rotation to move the jaws axially and concomitantly inwardly and outwardly in the slideways for size adjustment of the jaws between open and closed positions.
U.S. Pat. No. 5,067,376 to Gregory Fosella describes an adjustable wrench which has a drive shaft adapted to be turned by a conventional ratchet wrench. A housing is mounted on the output end of the shaft and three equidistantly spaced jaws are mounted between the shaft and surrounding housing. Cam surfaces are on the jaws and inside of the housing so that housing rotation in one direction will open the jaws and in the other direction will close them. A ratchet mechanism connects the shaft to the housing.
U.S. Pat. No. 5,375,489 to Travis McClure describes an automatically adjustable socket transferring torque a range of bolt heads sizes in either direction which comprises a pair of jaws slidable angled to a center cylinder and urged outward to a receiving position so that when the socket is set upon a bolt head the bolt head impresses the jaws towards the center cylinder, angularly so that the jaws maintain a parallel orientation to the bolt head faces. An upper cylinder and a lower cylinder surrounding the center cylinder each having complementary double arch rims interact as torque is applied to the upper cylinder, first to separate the two cylinders the bottom cylinder further impressing the jaws upon the bolt head until the jaws are maximally closed upon the bolt head the double arch rims then providing a torque transfer means from the upper cylinder to the lower cylinder. The lower cylinder transfers torque to the jaws through torque transfer surfaces to the jaws tangential to the bolt head. The invention also contemplates adapting jaws gripping surfaces to transfer torque to other configurations of objects to be torqued and adapting the socket to different sources of torque.
U.S. Pat. No. 5,386,749 to Kwang-Moo Kim describes a socket for a socket wrench comprising a socket body having a socket cavity formed at a lower portion of the socket body to extend vertically and a through hole, a pair of facing half sockets with different sizes fitted in the socket cavity to slide vertically, and an adjusting mechanism provided at an upper portion of the socket body and adapted to selectively adjust the vertical slide movements of the half sockets. The adjusting mechanism includes an adjusting member having an upper rod portion inserted into the through hole of the socket body such that its upper end is outwardly protruded from the through hole and a lower adjusting portion having a lower end of a long oval shape, a compression coil spring fitted around the upper rod portion and adapted to urge the adjusting member downward, and an adjusting knob including a coupling hole for forcedly fitting the protruded upper end of the upper rod portion of the adjusting member therein and a lug formed at a lower surface of the adjusting knob and adapted to temporarily fix the position of the adjusting member.
U.S. Pat. No. 5,996,446 to Han Young Lee describes a size adjustable wrench socket which is disclosed which has a plurality of jaws which are slidably engaged within a jaw guide for moving radially inward and outward relative to the jaw guide for fitting threaded fasteners of various sizes. A controller sleeve is configured for engaging upwardly extending protuberances of the jaws, such that rotation of the controller sleeve in various directions will have moved the jaws inward and outward relative to the jaw guide. The jaws further include a plurality of upwardly extending teeth which are formed into planar shoulders of intermediate portions of the jaws. A latch member is provided having a planar surface from which a plurality of teeth downwardly extend for engaging the upwardly extending teeth of the planar shoulders of the intermediate portions of the jaws. The latch member is movable from a latched position to a released position. When disposed in the latched position, the teeth of the latch member engage the upwardly extending teeth of the jaws to latch the jaws in a fixed position relative to the jaw guide. In the released position, the teeth of the latch member are spaced apart from the teeth of the jaws such that the jaws are movable relative to the jaw guide. The teeth of the jaws and the jaw guide are sized to provide indexed positions at which the jaws are spaced apart to correspond with predetermined, standard sizes of drive heads for threaded fasteners.
U.S. Pat. No. 6,000,300 to Walter J. Plamondon describes an adjustable socket wrench which has only two components, namely, a collet driver with movable jaws and a circumscribing adjustable sleeve. Positive detent positioning of the fastener engaging jaws is obtained by rotation of the adjusting sleeve which radially moves the jaws inwardly or outwardly without axial movement of any parts.
Notwithstanding the prior art, the present invention is neither taught nor rendered obvious thereby. The aforesaid prior art describes many forms of adjustable wrench arrangements, yet none teach or suggest the present invention device using three symmetrical, single piece xe2x80x9cshoulderxe2x80x9d units which simultaneously create surface-to-surface contacts on all six sides of a fastener, point-to-point symmetric contacts on three points of the fastener, and xe2x80x9cshoulderxe2x80x9d the three contacted points with a surface-to-surface, point-to-point, surface-to-surface arrangement with a single jaw.
The present invention is an adjustable head wrench which may be attached to a manual drive mechanism or a power drive mechanism. It includes an attachment feature for connecting it to the drive and has a main body which contains three symmetrically arranged jaws. These three jaws each have two adjacent gripping surfaces which form an angle of about 120xc2x0 to accommodate corners and adjacent surfaces of a hexagonal fastener, such as a hex screw, bolt or nut. The three jaws open and close by rotation and counter-rotation of an adjuster.
By the present invention, advantages not realized heretofore are achieved in adjustable heads. These include, simultaneously:
(a) all six sides of a hexagonal fastener are contacted (gripped) during engagement and torquing;
(b) three alternating corners of a hexagonal fastener are contacted during engagement and torquing;
(c) all six of the flats (flat surfaces) of a hexagonal fastener are contacted during engagement and torquing; and,
(d) one corner and the two adjacent flats (one on each side of the corner) of a hexagonal fastener are contacted during engagement and torquing by a single law to achieve continuity of a surface-to-surface, point-to-point, surface-to-surface engagement.